Amphineurus (Rhamphoneurus) nonnullus Alexander, 1967

Santos, Daubian, Santos, Rodrigo dos Reis & Ribeiro, Guilherme Cunha, 2022, Systematics of Amphineurus (Rhamphoneurus Alexander) (Diptera: Tipuloidea: Limoniidae), Arthropod Systematics & amp; Phylogeny 80, pp. 439-494 : 439

3.3.17. Amphineurus (Rhamphoneurus) nonnullus Alexander, 1967

Amphineurus (Rhamphoneurus) nonnullus Alexander, 1967: 491 (description); Alexander, 1968: fig. 17 (male terminalia).

Material examined.

Holotype: ♂, Chile, Chiloé Is., Aucar [42°9′S 73°30′W], 6/ 15-I-1952, Peña, Holotype 9619 (USNM) [part of specimen pinned and part in slide prepared by C.P. Alexander]. - Additional material: CHILE. 1 [sex unknown], Chiloé Is., Chaiten [42°58′S 72°32′W], 5/ 8-II-1954, Peña (USNM)*; 1 [sex unknown], Chiloé Is., Chepu [42°2′S 74°1′W], 1/ 3-II-1952, Peña (USNM) *.

Diagnosis.

This species is distinguished by R2 without a dark spot and the beginning of M1 desclerotized. Furthermore, the species has a distinctive male terminalia with a curved sheath of aedeagus with the branches of the clasper of different sizes.

Redescription.

Wing length 5.58 mm, width 1.71 mm. - Coloration: General coloration brownish-yellow. Rostrum and palpus dark brown. First segment of antenna yellow, remaining segments brownish-yellow. Head brown. Eyes grayish black. Thorax brownish yellow, pleura grayish-yellow. Scutum with one brownish-black stripe. Halter light yellow. Coxae light yellow; legs yellowish-brown. Abdomen yellowish brown. - Head (dorsal view Fig. 22B , ventral view Fig. 22A ): Rostrum bifurcated with short appendices; first palpal segment shorter than terminal segment; scape thinner than pedicel, terminal flagellomere as long as penultimate. - Thorax (lateral view Fig. 22E , dorsal view Fig. 22F ). Laterotergite almost triangular, anatergite taller than katatergite. Halter with dilated knob. Wing (Fig. 22D ) without distinctive markings; veins near fork of bM (Fig. 22C ) faded; m-cu inserted distal to fork of bM; M1+2 shorter than basal deflection of M1; R2+3 longer than R2+3+4. - Male terminalia (Fig. 22G ): Male tergite IX slightly darkened on distal margin, with wide median U-shaped notch; posterolateral lobes rounded. Dorsal branch of gonocoxite half-length of ventral branch; both branches setose. Lobe of gonostylus with rounded lobule; lobule about as long as half-length of lobe of gonostylus, narrower than stem. Clasper of gonostylus with differently shaped branches: lateral branch straight; medial branch curved, club-shaped. Mesal lobes of gonocoxite asymmetrical; both mesal lobes with sharp, 90° turn on posterior end; right mesal lobe significantly longer than left. Sheath of aedeagus curved, darkened only at distal portion.

Remarks.

This species resembles A. (R.) apiculatus Alexander but differs mainly in the fork of bM, shape of male tergite IX, clasper of gonostylus and mesal lobe.

Figures

Figure 22. Amphineurus (Rhamphoneurus) nonnullus Alexander. A head (ventral view); B head (dorsal view); C detail of wing; D wing; E thorax (lateral view); F thorax (dorsal view); G male tergite IX (dorsal view) and remainder of male terminalia (lateral view). - Abbreviations: aed sh, sheath of aedeagus; anatg, anatergite; anepm, anepimeron; anepst, anepisternum; aprn, anteropronotum; cgonst, clasper of gonostylus; cx, coxa; goncx, gonocoxite; hlt, halter; k, knob of halter; kepm, katepimeron; kepst, katepisternum; ktg, katatergite; l ms, left mesal lobe of gonocoxite; lgonst; lobe of gonostylus; mr, meron; mtanepst, metanepisternum; mtepm, metepimeron; mtg, mediotergite; mtkepst, metakatepisternum; mtn, metanotum; p, posterior basalare; patg, paratergite; pprn, postpronotum; presct, prescutum; r ms, right mesal lobe of gonocoxite; sct, scutum; sctl, scutellum; t 9, male tergite IX.